From karla:Solar (photovoltaic) cells convert sunlight directly into electricity. If solar cells were 100% efficient, they would generate about 1000 watts of power per square meter of surface area when exposed to direct sunlight. With lower efficiency, they generate proportionally less power. For example, 10% efficient cells generate 100 watts of power in direct sunlight. Suppose you want to supply 22 kilowattss of power to a house by putting solar panels on its roof. For solar cells with the average power of 49 watts per square meter of solar panels, how many square meters of solar panels would you need? Assume you can make use of the average power from the solar cellsAnswered by Penny Nom.

From angelo:hi admin please help me answer this question. thank you!
At a certain instant of time, the angle A of a triangle ABC is 60 degrees and increasing at the rate of 5degrees per second, the side AB is 10cm and increasing at the rate of 1cm per second, and side AC is 16cm and decreasing at the rate of 1/2 cm per second. Find the rate of change of side AB?Answered by Penny Nom.

From Shuvo:The diagram shows a vertical cross-section of a container in the form
of an inverted cone of height 60 cm and base radius 20 cm. The circular
base is held horizontal and uppermost. Water is pursed into the
container at a constant rate of 40 cm3/s.
Show that, when the depth of water in the container is x cm, the
volume of the water in the container is (πx^3)/27 cm3.
Find the rate of increase of "x" at the instant when "x" = 2.Answered by Penny Nom.

From Maria:Hi -
My husband gave me a new Samsung Galaxy mobile for out anniversaire gift. He set me a challenge which I have to solve before I can use the Phone. He has set the pin code with numbers 4, 7 and 0 and created a four digit code with the said numbers. Is there a way I can somehow list all possible combinations and try them all? Thanks!Answered by Penny Nom.

From Oyewumi:Mr A sold a car to Mr B at 20% profit margin and Mr B sold the car to Mr C at 30% markup on cost. If Mr C got the car at $x.
1. How much did Mr A buy the car in terms of x.
2. How much did Mr A buy the car if x is $2800000Answered by Penny Nom.

From Natalie:I'm in 4th grade and two weeks ago my class learned how to use compatible numbers.
I was REALLY confused but I didn't want to say I didn't understand because I just wanted to go home.
Tomorrow we have the Topic 7 Test and I'm stuck on a problem that requires using compatible numbers.
My mom apparently hasn't heard of compatible numbers and she can't really help me too much.
Here's the problem : The local library places new books in a section with 31 shelves. Each shelf
fits 18 books. Use compatible numbers to estimate the number of books that the library can fit on
the shelves.Answered by Penny Nom.

From Robin:I am wondering if you can explain in layman terms how to figure out how many different ways the numbers 00-99 can be arranged? The discussion that sparked this question revolved around the practice of retiring athletes numbers and how many actual number combinations there are. So if I were to use 00, 01, 02 03, 04, 05, 06, 07, 08, 09, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, ....99. I say there are only 109 different numbers. I'm being told I'm wrong that there are way more than that. Please help. Thank you, RobinAnswered by Penny Nom.

PLEASE HELP WITH THIS VERY DIFFICULT STATISTICS QUESTION(the process would really help)
Imagine you and your 4 study group partners are interested in whether all
those hours you spent together working on statistics problems for midterm
exam 2 actually helped your group's performance on that exam relative to its
performance on the first midterm exam. Suppose the first and second midterm
grades were as follows:
Is there sufficient evidence (at a = :05) to conclude that the group performed
better on midterm 2? Please provide all your calculations.

From Dale:I'm needing to find the square footage of an irregular pentagon.
I've seen the other questions similar to this one, but without a great deal of difficulty can't get you the angle degrees, or the length between opposing angles.
I'm hoping that a different bit of information can help. So here goes:
The longest side is 67ft long.
One of its legs is 39ft long, and the other is 18ft long.
The leg off of the other end of the 39ft leg is 35ft long.
The leg off of the other end of the 18ft is 49ft long, and meets the other end of the 35ft side.
The information that I DO have, which I'm hoping makes the difference, is that the 39ft and the 18ft sides are parallel.
Also, while the angles at each end of the 67ft side are not right angles, they are fairly close to it,
approximately 80 degrees at the 39 ft side corner, and 100 degrees at the 18ft side corner.

From Chuck:I'm building a custom range hood and can't seem to get the angles correct where the front and side panels intersect.
I saw a similar post but there's no way I can do the calculations for a Wolfram Alpha!

Here are the dimensions that I have (in inches)...

Base - Front 29 7/16" x side 19 3/16"
Top - Front 10" x side 9"
Front Panel Length (from base to top on an angle) 21"
Side Panel Length (from base to top on an angle) - 17 9/16"
Vertical distance from the base to the top 14 1/4 inches.

Any help finding the bevel/miter of the two front corners where the sides meet the front panel would be greatly appreciated.

From rukhsar:A certain triangle has sides, which are, respectively, 6 inches, 8 inches, and 10 inches long. A rectangle equal in area to that of the triangle has a width of 3 inches. The Perimeter of the rectangle, expressed in inches, isAnswered by Penny Nom.

From rukhsar:A certain triangle has sides, which are, respectively, 6 inches, 8 inches, and 10 inches long. A rectangle equal in area to that of the triangle has a width of 3 inches. The Perimeter of the rectangle, expressed in inches, isAnswered by Penny Nom.

From Duncan:HI - I've added up the GST from a pile of receipts and would like to know what the total cost of goods would be without GST. I don't want to add up 100's of receipts again with the cost before GST but I do need this total cost.
i.e.) I know I paid $400 GST, what would the formula be to find out the cost of what I purchased before taxes? Your help is much appreciated!Answered by Penny Nom.

From Duncan:HI - I've added up the GST from a pile of receipts and would like to know what the total cost of goods would be without GST. I don't want to add up 100's of receipts again with the cost before GST but I do need this total cost.
i.e.) I know I paid $400 GST, what would the formula be to find out the cost of what I purchased before taxes? Your help is much appreciated!Answered by Penny Nom.

From Natasha:Veronika works at Future Shop and earns ₱10.50/h plus 6% commission on sales. Last week Veronika worked 40 hours. What was Veronika’s weekly gross salary if her total sales were ₱2050?Answered by Penny Nom.

two answers were given... I believe both to be incorrect.
five bales weighed two at a time: weightx2 given: 110,112,113,114,115,116,117,118,120, and 121. It stated all combinations ie: ab,ac,ad,ad,bc,bd,be, etc. to arrive at the above 10 combined weights. I come up with the following...

From Roberto:I am trying to build a "ring" for our remote control boats, using irrigation pipe.
I'd like to use full 20' long sticks for the long sides and use eight of what we call
45s, which are actually 135' fittings to make the six short sides. If I know the length
of the two long sides, what would be the formula to find the exact lengths of the short sides?

From John:http://mathcentral.uregina.ca/QQ/database/QQ.09.06/sylvia1.html
In the initial assumption of that proof, root 6 is assumed to be a/b where a and b have no common factors, but why does having a common factor make it irrational?Answered by Penny Nom.

From carolyn:the equation 2y + 53 = 165 represents the situation joel spent 165 dollars on a pair of jeans and two shirts at the same price what does y represent
price of a pair of jeans
price of a shirt
amount joel spent on the shirts
number of shirts joel boughtAnswered by Penny Nom.

From Michelle:In 2016 there were about 135 million households in the United States. 36.5% of the households own at least one dog. On average, these households have 1.6 dogs. How many millins of pet dogs were in the United States in 2016?Answered by Penny Nom.

From Justina:At 2:20 p.m. Jack is at the top of the hill and starts walking down at the exact same time that Jill, who is at the bottom of the hill, starts walking up. If they maintain the uphill speed of 2mph and downhill speed of 4mph and the distance from the bottom to the top of the hill is 1.5 mi, at what time will Jack and Jill meet?Answered by Penny Nom.

From justina:Jack and Jill travel up a hill at a speed of 2mi/h.they travel back down the hill at a speed of 4mi/h.what is their average speed for the entire trip? express your answer as a mixed numberAnswered by Penny Nom.

From SM:How many guests were present at an Italian dinner if every 2 guests shared a bowl of salad, every 3 guests shared a bowl of pasta, and every four guests shared a bowl of meatballs, and there were 65 bowls used altogether?Answered by Penny Nom.

From Maria:There are a total of 270 peanuts divided up into five different bags. The first two bags contain 174 peanuts between the two of them. The second and third bags contain 130 peanuts between the two of them. The third and fourth bags contain 86 peanuts between the two of them. The fourth and fifth bags contain 42 peanuts between the two of them. How many peanuts are in each bag?Answered by Penny Nom.

I am stuck on a maths question in which it is asking, how to find the angle between two given planes. These planes are in a 3D shape such as a prism.
How can I do this?
Please reply as soon as possible

From paul:trying to determine volume of an attic base is rectangular 29 ft by 37 ft
peak runs parallel to longest base side and is 7 ft long
roof lines run from each end of the peak to the respective corners
the peak is 3.5 ft above the base
(so seen from above there are 5 visible lines: the peak and 1 line to each of the 4 corners)Answered by Harley.

From Lisa:I am applying for a job that pays $16.00 per hour, plus 5 hours of overtime every 2 weeks. I live in California, where overtime is 1.5 times the regular rate of pay after you work 8 hours a day. What would the gross annual salary be with all the overtime hours added in?Answered by Penny Nom.

From Ken:A car is driven on a rough road at a speed of 25km and then on a concrete road with a speed of 70kph. The car has 5.5 hours to travel 225km. How long did the car travel on concrete road?Answered by Penny Nom.

From Ramzan:a diagram shows the shape of rectangular framework with length (2x+20)cm and with (y+10)cm . The outline is made of wire . If a circle with diameter 56 cm is to be made from the wire and the area of the rectangle is 420 square centimeter ,find the possible lengths and width of the rectangleAnswered by Penny Nom.

From Christopher:math team has 20 people on the team but only 4 can enter the competition. The team captain has to pick 4 of them but he knows that he cannot put James, Bill or Todd on the team with one another or there will be problems. what would the formula be to find the solution to how many possible team combinations the areAnswered by Penny Nom.

From Ian:The arch of the bridge is in the shape of semi ellipse,with its major axis at the water level.suppose the arch is 20ft. High in the middle,and 120 ft. Across its major axis. How high above the water level is the arch,at a point 20 ft.from the center (horizontally). Round of 2 decimal placesAnswered by Penny Nom.

From Gerry:Looking to make a full size template for an arched window. Need increments every 16". The radius is 138' 0 9/16" , the chord is 226" and the rise at center of chord is 43"Answered by Penny Nom.

From Josh:Marie, a police officer, spots a speeding car and starts chasing it. The speeding
car travels at a speed of 130 feet per second. Marie's car reaches a constant speed
of 145 feet per second 1725 feet from the start of the chase. During that time, the
speeding car has traveled 3150 feet. Write a system of equations to represent this
situation.Answered by Penny Nom.

From liezel:what is the answer of this problem, If Catherine and molly has 320pesos altogether, Molly and tom have 360 in all. Tom and Catherine have 240pesos altogether.How much does each of them have?Answered by Penny Nom.

ive been trying to do this task but i have no idea how to do it
the question is
Find the common difference and the n^th term of the arithmetic sequence if the first term is 4 and the twentieth sum of the terms is 1030Answered by Penny Nom.

From Tront:So, there's a general rule that all squares are rectangles but not all rectangles are squares. Im trying to find a term that would describe this relationship. I've found that if all of A is B but not all B is A then I'd say that A is a subset of B, but is there a term that describes the relationship as a whole? I don't want to describe the components, I want to describe the relationship as a whole.Answered by Penny Nom.

Why is it recommended to move the decimal from a divisor when dividing so that the divisor is a whole number?
I know how to divide by moving the decimal from the divisor, but I cannot explain the reason.

From Jamal:A man drives from Ibadan to Oyo a distance of 48km in 45 minutes. If he drives at 72km/h where the surface is good and 48km/h where the surface is bad. Find the number of kilometers of good surfacesAnswered by Penny Nom.

From Angela:Following is a problem from my 3rd grader's homework assignment:
Solve. Draw a diagram to represent the situation.
Rachel has 20 one-inch beads. She wants to use all of them to make a square picture frame. What will be the length of each side?
Find Perimeter, Area, and Side LengthAnswered by Penny Nom.

From Va:hello, can you pls help me....i have a property which has 300 ft width road frontage and my lot is 4700 ft deep to the back line of my property which i am told 27 acres. I want to only sell 25 acres...and go to the rear line with 4700 feet, but decrease the front width using the 300 ft measurement. how do i decrease the 300 ft width measurement by 2 acres? i am confused what the measurement would be..thank you....so to sum it i want to make 25 acres out of a measurement of 300 x 4700 ft long reducing the front measurement..thank you so much.Answered by Penny Nom.

From Annelle:a body is thrown vertically downward from a height above the ground. determine the initial velocity and the height of the starting point if after 4 secs it reaches the ground with velocity of 68 m/s.Answered by Penny Nom.

From Kameron:I have been given a challenge problem that states that Diameter AB is drawn in a circle if 10 inch. Chords AC and BD are drawn so that each is of length 12inch and ACDB is a trapezoid. Find the height, in inches, of the trapezoidAnswered by Penny Nom.

From Bill:I need to find the height of the intersection point of two building wires< br />
Building A is 860 feet high and building B is 480 feet high. The wires existent from the top of one building to
The bottom of the other < br />
The distance between is 32 feetAnswered by Penny Nom.

From Joel:Find a formula to calculate the circumferences of an inverted bowl at various heights.

E.g. Take an inverted bowl with a diameter of "x" cm and a depth / height of "y" cm.

How can I calculate the circumferences at distances of various heights above the base?

Alternately, what would be the formula to calculate the distance of the line segment resulting from a line which intersects both sides of a parabola in which that line is drawn parallel to the tangent of the vertex of the parabola at any given distance from the vertex?Answered by Penny Nom.

From Raquel:A minor league baseball team gave away baseball cards to each person entering the stadium. One group receives 28 baseball cards. A second group received 68 baseball card. If each person entering the stadium receive the same number of cards, what was the greatest possible number of baseball cards that each person could have received?Answered by Penny Nom.

From Sam:I have a locked iPhone and it has all my of my holiday photos on it. I changed the password and then I think I did a incorrect number pattern but anyway I know it ends with 99 and the first 4 digits are 235 and 6 could you please send all of the combinations for this password (without the 99) Thx and plz get back ASAP I need it for schoolAnswered by Penny Nom.

From Tasha:A sector of a circle subtends an angle of 216 degrees at the centre, If this sector is used to form a cone of vertical height ,8cm, calculate the base radius of the coneAnswered by Penny Nom.

From Mohammed:I bought a 2 mm sheet plate of 1.2m × 2.4m in fijian $95. I used 1.95m × 0.4m from that sheet plate. What will be my total cost for the sheet plate I used. It was a mild steel plate.Answered by Penny Nom.

From Randolph:Hi, On your calculator I found that a box 10 by 10 by 10 inches has a volume of 1,000.0000000000001 cubic inches. Can you explain the numeral 1 thirteen places past the decimal? Thanks, RandyAnswered by Penny Nom.

From Maximilian:Hi, i have a strange issue with the phrase "faster than" in percentage, ie. if i have a 10MB/s connection, and somebody has a 7MB/s connection, is it 30% faster or 50% faster.-
which ( affirmation, phrase, sentence ) is the right one:

a:) My 10MB/S connection is 50% faster than the 7MB/s ?
or
b:) My 10MB/S connection is 30% faster than the 7MB/s ?

Thanks in Advance, and please if you can teach me why !Answered by Penny Nom.

From Émile:If you had 2^a = 4 and 2^b = 4 you could assume that a = b right? Yet we can observe that 1^1 and 1^0 both equal 1, yet 1 = 0 isn't true. So if given a log base 1 number 1 the would the answer be 1 AND 0?Answered by Penny Nom.

From Sunni:I'm working on a graph and I need to find the percentage of increase from one figure to another. How do I do that? For instance our department started with a workload of 1773 in Jan and ended with 341 in Dec. In addition to that we received 2088 new items from Jan - Dec with an average of 5 workers. How do I find the percentage of increased productivity if any?Answered by Penny Nom.

From michael:I was teaching my student about exponent when we stumbled across this problem.

"write (-125)^-3 in exponent form"

The problem is with the number "-125". I think -125 = (-5)^3. But one of my student thought that it is -125= -5^3.
Both of them is equal to -125 but they totally different in structure. I wonder which one is correct and why it is. I am worried if they get this wrong, it might spell problem in the future when we start substituting the numbers with variable.
Thank you very much for reading my question and answering it.Answered by Penny Nom.

From Kenneth:Hello, I have a question for you. I have a special needs daughter and I want to install a ceiling fan into her room. The fan is 42 inches in diameter. I would like to build a wooden hexagon enclosure to protect the fan. I would like the enclosure to be at least 2 inches wider than the fan on each side measuring from flat surface across to flat surface. How do I figure out the length of each panel so that I can miter them and assemble it? Thank you for your time.Answered by Penny Nom.

From DEANNA:I am trying to cover a 16 x 31 foot ceiling with tablecloths. For sale, are 90 x 132 inch tablecloths for $4.97 a piece and 60 x 102 inch tablecloths for $3.85 a piece. Which would be my cheapest option to cover the entire space?Answered by Penny Nom.

From Charlene:A large hose will fill a pool in 40 minutes while it takes a smaller hose 60 minutes to fill the same pool. The same pool takes 80 minutes to drain if the drain is open. Suppose one day both the hoses are turned on, but by accident the drain was left open. How long would it take to fill the pool that day?Answered by Penny Nom.

From Brad:Kristina invests a total of $27,500 in two accounts paying 5% and 7% simple interest, respectively. How much was invested in each account if, after one year, the total interest was $1,645.00.Answered by Penny Nom.

From ron:if a vehicle travels 50 feet in 2.5 seconds what is the speed in mph.
3600 sec in hour /5280 feet in a mile i get .68181818. how do i figure the 2.5
seconds. all the calculators I've used show 34 mph is that correct or am i forgetting the 2.5 second. please help.Answered by Penny Nom.

From Russell:Working with a segment of a circle. The O.D. is 3.440" the length of the chord is 3.130 I need information on the volume of the largest area. I would like to know (in thousands of an inch) how tall would the largest area need to be to equal .1143 cubic inches If you need more info I can send it Thanks in advanceAnswered by p.

From Bob:(1) I have a net price item at $4,664.66 but do not have the discount percentage. I have been told I received 40%? How do I establish the original List Price and to confirm what discount I received?Answered by Penny Nom.

From Desiree:Vacation Rentals rents electric carts for travel on their grounds. The economy plan rents
carts for $26 per day and the premium plan rents a carts for $12 per day plus a one time fee of $126.05
For how many whole days would it be cheaper to rent from the economy plan then from the premium plan?Answered by Penny Nom.

From Rand:It is most likely already been answered but I can not seem to find the right key words for the search engine?.

What I am looking for is, if you have an have arch/arc and you know the degree of slope and the height of the arch/arc from ground lvl; how do you factor the decreasing angle/#’s to get the distance tween the two feet on the assumption that the arch/arc is curved all the way to ground lvl?

a. where the legs widen continuously (till they hit ground) so yes parabolic &
b. where the legs come down straight after a ½ circumference run.

From Pat:So... I'm trying to draw up a plan for my new kennel buildings. They are going to built
out of grain bins. I know, cool,... right. Anyway the kennels will be along the outside
of the circle and be shaped like wedges. the center will be a play area. All of the kennel
sides are 6 ft in length so the size of the gate will determine how many kennels I can
fit in each bin. If I want to put an odd number of kennels in and I cant draw
a straight line across to make all of the wedges the same size... how do I figure out the
angles...degrees ? maybe i'm making it too hard but i'd like to give the dogs as much space
as i can. I did up some ... attached.Answered by Harley Weston.

From Shambhavi:A long wire of some length is cut into small pieces of 216 cm leaves a small piece of length of 89 cm of this part were cut into equal pieces each of 18 cm the length of the left over wire would beAnswered by Penny Nom.

From Kathryn:A trough is 6 m long, and has uniform cross-section of an equilateral triangle with sides 1 m.
Water leaks from the bottom of the trough, at a constant rate of 0.1 m3/min.
Find the rate at which the water level is falling when the water is 0.2m deep.Answered by Penny Nom.

From Chris:We have a square piece of wood (30 inches x 30 inches) that we need to cut into an octagon. Is there a simple way to figure out where to make the marks/points to cut? I mean like really simple?

From Salem:A fitness center offers a special price for group-class students. The cost of registration is 30 dollars and then you have to pay 25 dollars per month. What is the rule of the equation in the light of c=---m+----?Answered by Penny Nom.

From Jondi:I am trying to visualize 980 cubic yards of dirt by using a metaphor.
Would this be the size of a car?
A fire engine?
A semi-trailer?
How many trucks would you need to haul away 980 yards of dirt?Answered by Penny Nom.

From Halley:Two boats leave port at the same time. Boat A travels east at a speed of 12 km/hr. Boat B travels southwest at a speed of 14 km/hr. After two hours, how far apart are the boats? North is 0 degrees. How do I figure this out.
ThanksAnswered by Penny Nom.

If a sales tax of 7% is placed on every $1.00 of merchandise for sale, is it correct to indicate
the tax as 7%/ per $1.00 or 7%/$1.00? If the calculation is expressed as 7%/$1.00 X $5.00,
the tax is not $0.35 but 0.35. Is a tax rate of 7% incorrectly represented as 7%/$1.00
since the dollar unit cancels from the multiplication?

From Mahesh:A man purchases one shirt and one T-Shirt for Rs. 6000. He sells the shirt at a profit of 20% and T-Shirt at a loss of 10%, as a result he gains 2% on whole transaction. what is the cost price of the T-Shirt ?Answered by Penny Nom.

From Abbey:Starting from the same spot, one boy completed a route in 9 minutes and another boy completed it in 15 minutes. When will both boys be at the same starting point at the same time again?Answered by Penny Nom.

From Abigail:A garden measures 12 feet by 16 feet. The family would like to add a stone walkway around the garden. This would increase the total area of to 302.25 square feet. what will be the width of the of the walkwayAnswered by Penny Nom.

From Anandmay:Hello
I was looking closely at early arithmetic where I found how we discovered properties of Arithmetic.
Like:2 x 3 = 3 x 2.
This can be proved by considering a 2-D figure(actually,quadrilateral) having length consisting of 2 boxes of
1-by-1 dimensions and breadth of 3 boxes of the same dimensions.
Now,consider it again,but,this time,length of 3,and breadth of 2 of such 1 by 1 boxes.
We now notice that we can fit the 2 types of rectangles formed on each other precisely.
So the multiplicative property of commutativity is true for all natural numbers as we can generalize the result(in our mind,for self satisfaction).

Now,can you find me a nice satisfactory reason of why a fraction times a natural number equals the number times the fraction?
I mean, for example,i can understand the meaning of 3 x 2/3 to be three times 2-3rd,that is, 2/3+2/3+2/3.Fair enough.
But here is the problem:By definition and actual meaning of multiplication, a x b means the repeated sum of b,done 'a' times.
So what is the meaning of doing 2/3 x 3?The repeated addition of 3 how many times??2/3 times??Not making sense,right?And even
we have not proved yet the commutative property of numbers INCLUDING fractions.So how can we resolve this problem and make these things meaningful?
ThanksAnswered by Penny Nom.

From Anandmay:Hi!
I saw one of your answered questions:Why are equivalent fractions equal?
The same question I had for why i searched and ended up entering this wonderful site.
The answer was so much experimental based.I mean,for example,it was explained how
3/4 was equal to 6/8 by dividing a unit into 4 equal parts and taking four of the parts,and then dividing the
same unit into 8 equal parts and then taking 6 of them.The result was that both the taken parts were equal.
(That is,3 out of 4 equal parts were equal to 6 of the 8 equal parts.)
But,this was very much non-generalized and experimental-based result(proof).
And we all know that in mathematics,we confirm some particular thing for all the numbers iff we generalize
it.

So,can you explain more clearly 'HOW' the 3 parts of the 4 equal parts and the 6 of the 8 equal parts of the unit
equal(that is the same)?I don't want experimental proof.I want clear proof,and thus please give a generalized
proof for all fractions and their equivalents.
Thanks!Answered by Penny Nom.

Hello,
I am trying to find impressions on a roll (either full roll or partial).
Let's say I have the following information.
- Outer Diameter of roll
- Inner Diameter of roll (cardboard core)
- thickness per layer
- Each cut off length (impression length)

Now let's say a roll has a 40in outer diameter, the cardboard core has a 3.75in diameter and a thickness of .002. Each impression has a cut off of 14inches.
With this the roll will have approximately 2,700 impressions. How would I find the remaining impressions if the outer diameter of the roll is only 6.5inches?

From Brian:I am trying to determine the amount of a liquid remaining in a 55 gallon drum when it is tilted at 45 degrees and the liquid level is low enough so that the liquid does not completely cover the bottom of the drum.

From Aeriel:A lock works by having a key turn a sequence of tumblers. Consecutive tumblers have different heights, and in order to unlock the lock, the sequence of heights on the key must exactly match those of the lock. The picture below shows a lock with four tumblers.
How many different keys can be made for a lock that has 7 tumblers with 5 possible heights each?Answered by Penny Nom.

From yolani:two equal circles with centre A (1;1)and B (4;5)touch a third circle with centre P as shown in the diagram. If P ,A and B Lie on a straight line find the coordinates of PAnswered by Penny Nom.

From Brian:Two participants are alternatively selecting eggs from a basket of 6 hard-boiled eggs and 6 uncooked eggs.
Alternatively they are smashing the eggs on their foreheads. One participant gets 4 hard boiled eggs in a row and the other person gets 4 uncooked eggs in a row.
What is the probability of this occurring (I watched this happen).

From Bianca:x represents the number of hours since 8am. y represents the number of children the school nurse has seen during the school day. The nurse has seen 3 children by 8am and 27 children by noon.
How many children has the nurse seen at 2pm?
If the nurse has seen 18 children, what time is it?Answered by Penny Nom.

From Stephanie:Starting at 8:00a.m., a passenger plane leaves from an airport every 6 minutes and a cargo plane leaves every 7 minutes. When is the next time these kinds of planes will leave at the same time?Answered by Penny Nom.

From Myra:I don't know how to help my child answer this question - Selina bought a shirt on sale that was 20% less than the original price. The original price was $6 more than the sale price. What was the original price?Answered by Penny Nom.

So happy I found this site. I am having problems with bases. My question is :
Please perform the subtraction between two number over different bases :
A. (5874)base 12 - (216)base 9
B. (216)base 9 - (5874)base 12Answered by Penny Nom.

From tammie:Koch’s kinky curve is created by starting with a straight segment and replacing it with four segments, each 1/3 as long as the original segment. So, at the second stage the curve has three bends. At the next stage, each segment is replaced by four segments, and so on. How many bends does the curve have at the third stage?Answered by Penny Nom.

From Peter:I have seen your response to a similar question from Steve which Chris and Harley responded to, however I am not familiar with some of the terms. Is there a formula that I can enter my details in which will give me the specific angles I require. The item I am constructing is much larger than the one you responded to previously. Thank you for any assistance you are able to provide.Answered by Penny Nom.

From Kimberly:I have a tank that is shaped like a cylinder, and it has to hold 2 million
gallons of water. There is a height limit of 30 ft.
I know the equation is V=pi x r squared x h but I don't know if I need anything
For the square foot of water.Answered by Penny Nom.

From Kyla:Jenny cares 7 times as many butterflies as Charles.
Charles catches 2 times as much as Chase.
All together they have 560 butterflies.
How many butterflies does each person have?
Please help, I am very confused on how to solve the problem.
Thank you!Answered by Penny Nom.

From Ms.:Car 1 is traveling down the road at 50 mph and passes Car 2 is
sitting on the side of the road. Car 2 needs to catch Car 1 one half mile
down the road. How fast must Car 2 drive to catch Car 1 if Car 2
waits 10 seconds before pursuing Car 1?

Yes, the assumption is that the Car 2 can accelerate from a standing position and over take Car 1 rate. What is the answer or formula for this type of question?
Respectfully
Befuddled Mom?Answered by Penny Nom.

From Ms.:Car 1 is traveling down the road at 50 mph and passes Car 2 is
sitting on the side of the road. Car 2 needs to catch Car 1 one half mile
down the road. How fast must Car 2 drive to catch Car 1 if Car 2
waits 10 seconds before pursuing Car 1?

Yes, the assumption is that the Car 2 can accelerate from a standing position and over take Car 1 rate. What is the answer or formula for this type of question?
Respectfully
Befuddled Mom?Answered by Penny Nom.

From Ken:I have a roll that is 13.5 inches wide ( OD) , and is wound on a 3 inch core. the thickness of the material is 3.5 thick.
Do you know of a formula that can calculate the linear feet on that roll??Answered by Harley Weston.

From Brett:What is inside radius, in centimeters of a coffee cup if it holds 350g of coffee when filled to a depth of 9.5 cm? Assume coffee has the same density of water, 1.00g/cm3. A numeric value is expected and not an expression.Answered by Penny Nom.

From Hannah:The information provided is
---A ski slope has a slope of -0.2. You start at an altitude of 10,000ft.
Then the question is "Write the equation giving altitude (a) as a function of horizontal distance moved (d).
I know this is probably a very simple question but I didn't take a math class my senior year and now I'm a freshman in college, so some of it is very frustrating to me.
Any help is much appreciated, thank you!Answered by Penny Nom.

From Lily:Hi! I was wondering, I was having a little issue understanding this one problem. It was "write 81 in exponential 2 different ways" and I already got 9(2) but I was wondering what the second one could be! Thanks! -LilyAnswered by Penny Nom.

From Lisa:Three brothers spent different amounts of money on their recent vacation.
Matt spent $25 less than Todd.
Jeff spent 3 times as much as Matt.
How much did each brother spend if they spent a total of $275?

From Ting:The first four terms of a sequence are 4, 20, 56 and 120. By comparing with the nth term of sequence 1,5,14 and 30 which is 1/6n(n+1)(2n+1), find a formula for nth term. Can you precisely show out how you do this questions ( with the steps please)Answered by Penny Nom.

From sai:The main cable of a suspension bridge has the shape of a parabola. The cables are strung from the top of two towers, 61 metres apart, each 15.25 metres high above the roadway. The cable is 1.5 metres above the roadway at the point that is directly between the towers.

h(x)=a(x-30.5)^2+1.5
where a is the constant and its value to be determined.

a) determine the value of the constant a by using that the fact that height of the suspension cable, h(x) is 15.25 metres at each tower. Hence, write the updated model equation.Answered by Penny Nom.

From Kirby:A ship is sailing due west when a light is observed with heading 297°50' from the ship. After the ship has travelled 2250 feet, the light heads 311°55' from the ship. If the course is continued, how close will the ship approach the light?Answered by Penny Nom.

From Deniece:I have 2 lots that are joined together. One lot is 38' X 105' and the other is 45' X 105'. What is the total in acre size. Or, how close are these lots to make one full acre? I want to sell both lots and want to advertise using the total lot size. Thank you.Answered by Penny Nom.

From justin:Carlos, Mark, Jeremy, and Alan all collect Yugioh cards. Mark has twice as many cards as Jeremy. Carlos has 3 times as many cards as Jeremy, and Alan has collected 12 less than 3 times as many cards as Jeremy. Together the four players have collected 456 cards. How many does each person have?Answered by Penny Nom.

From anonymous:A cone is inscribed in a hemisphere. the slant height of the cone is 20cm. When cut along its slant height, the cone forms a sector of a circle.
find the angle of the sector, to the nearest 1 decimal place.Answered by Penny Nom.

From Shriya:The first term of a sequence is 13.
The following terms are found by alternately adding 4 and 6 to the previous term.
The first six terms are 13 17 23 27 33 37.
Find the 80th term.Answered by Penny Nom.

From Mehzad:Every day, the temperature in a greenhouse is at its low temperature, 70 degrees Fahrenheit, at 2 a.m. and at its high temperature, 84 degrees Fahrenheit, at 2pm. Its temperature increases linearly between 2 am and 2pm , and decreases linearly from 2 pm and to 2am. The outside temperature follows the same linear patterns, but has a low temperature of 60 degrees Fahrenheit at 2 am and a high temperature of 78 degrees Fahrenheit at 2 pm. At which of the following times will the temperature inside and outside the greenhouse be the same?

a) 8:00 am
b) 12:00 noon
c) 4:00 pm
d) The two temperatures will never be the sameAnswered by Penny Nom.

From Sayari:Hello.
Is it possible for two right angled triangles to have the same length of base and height and a different hypotenuse? If not so, then why in the congruence criteria RHS the hypotenuse is given more importance? It can also be like- 'two triangles are congruent if they are right angled and have the same base and height.'
Thank You.Answered by Penny Nom.

From carol:a train leaves Erie with twice as many women as men. At York, 17 men get on and 16 women . How many men and women were originally on the train?off. There are now the same number of men as womenAnswered by Penny Nom.

From Scott:If I have a 16 x 32 rectangle the square feet is 512. So if I take a rope 96 feet long , which is the lineal feet of the rectangle, and manipulate it to any shape I want does the square footage inside the rope stay at 512 square feet? Thanks in advance!Answered by Penny Nom.

From Gordon:Some authorities treat "triakis" (and related terms "dyakis", "tetrakis", etc.) as attached prefixes; others treat them as separate adjectives. Thus I see one of the Catalan solids described as both "triakistetrahedron" and "triakis tetrahedron". Which usage is correct?Answered by Chris Fisher.

From abhay:The speeds of John and Max are 30 km/h and 40 km/h.Initially Max is at a place L and John is at a place M. The distance between L and M is 650 km. John started his journey 3 hours earlier than Max to meet each other. If they meet each other at a place P somewhere between L and M, then the distance between P and M is?Answered by Penny Nom.

From Fiona:Hi the question i have is, if I have a cylinder filled with water and the volume of the water is 150Pi what would the rise in the level of the water be if you put a sphere into the cylinder with a volume of 500/3Pi? Sorry if it's a bit long windedAnswered by Penny Nom.

From Render:Fred cuts a 12- inch piece of rope. Then he cuts a second piece of rope that is 3/2 longer than the first piece. Is the second piece shorter or longer than the first piece? Explain.Answered by Penny Nom.

From Clarice:A trough having an equilateral triangle end sections has sides equal to 0.4 m and 7m long.what is the volume of the liquid in the container if the depth of the water is one half the depth of the trough?Answered by Penny Nom.

From Aaron:I want to make a table with a puzzle embedded in it. The table top would be a
36" circle and the puzzle is 20"x27" I'm thinking that it's not going to fit,
but not sure. Any help would be appreciated.
Thanks,
AaronAnswered by Penny Nom.

From Paul:How do you calculate a partially filled truncated rectangular pyramid if you always know the bottom rectangle, the maximum height top rectangle perimeter, but have a varying height. Similar to filling up a pond you know the current height and dimensions at the max rectangle how do you calculate it half full i.e. 10x30 outside perimeter with a 2x8 base and a max height of 6ft how do you calculate it at 3ft without re-measuring the top perimeter.
Thanks,
PaulAnswered by Harley Weston.

From Laura:At 11:00 a.m., Jake started driving along a highway at constant speed of 50 miles per hour. A quarter of an hour later, Sara started driving along the same highway in the same direction as Jake at the constant speed of 65 miles per hour. At what time will Sara catch up with Jake?Answered by Penny Nom.

From Jan:A rectangular field is 63m long and 21m wide. A fence of 2m in height is needed to fence the field and fencing is also required to divide the field in three square sections. There are three wooden gates measuring at 1.5m to the three sections of the field. What is the total surface area of the fence needed for fencing and diving the field?Answered by Penny Nom.

From Ralph:How many combinations are possible if a "safe" has four buttons and you can use a six digit code? (these are just single press buttons..)For example, this could be one possible combination: Button 4 Button 1 Button 1 Button 3 Button 2 Button 4. Thanks!Answered by Penny Nom.

From Joel:I am bored with what I'm learning in 6th math class and want a challenge. I decided to look at trig. I couldn't find a good resource to teach me. Could someone either explain trig to me or show me a resource? Please don't say I'm too young to learn trig. I just am trying to learn.Answered by Penny Nom.

From Carla:if a pump house that measures 20'x16' sits in the middle of a site that is 50'x60' and you apply crushed rock to the site at depth of 6", how many yards will you need to haul?Answered by Penny Nom.

From Renae:Charity has 42 more pennies than dimes. Hope has 7 times as many pennies than dimes. Hope and Charity have the same number of dimes. Together they have $5.46. How many dimes and pennies do each have?Answered by Penny Nom.

So, there is a circle. In the circle, there is an equilateral triangle inscribed.
Each side of the triangle is 20. There is no other info given, other than
the triangle is inscribed in the circle and the sides of the triangle are 20.
I am supposed to find the radius of the circle! Please help!Answered by Penny Nom.

From Vishal:Total amount paid annually $444 for 2014 which is inclusive for tax.
tax rate for first six month is 7% then it is changed to 15% for second six months.
calculate the total basic amount paid before tax.

the basic amount on which tax paid in first and second six month is same.Answered by Penny Nom.

From Isiah:So I am working on a problem with a few friends; you have an arc with the center of its chord at 0,0. We also have a known sagitta and a known radius of curvature.
How do we calculate the height extending in both the positive and negative directions?
Central sag: 2.48
Chord length: 9.6Answered by Penny Nom.

From Harold:I need to slope a area of my yard away from my house and garage. The length of my house is 80 feet long and i need to slope it 22 feet away. I want to raise the dirt at the foundation by 6 inches and slope it down to nothing at the width of 22 feet. How much soil would i require?Answered by Penny Nom.

From Marc:While on a road trip I imagined this random word problem. Suppose I start a trip of 75 miles. My initial speed is 75 miles per hour. After every mile traveled I decrease my speed by one mile per hour. After the first mile I decrease my speed to 74 miles per hour and so on for each subsequent mile traveled. How long will it take to complete the 75 mile journey?Answered by Penny Nom.

From Richard:I cannot understand why if you have a perimeter say of 4 units as the circumference of
a circle then you reshape it into a square you lose very approximately some 20% of its
volume but the perimeter length stays the same.
Can you please explain this to me as to why the volume decreases.Answered by Penny Nom.

From BETH:i am trying to cover an area for a 15x15 foot round pool with play sand before I set up the pool. My playsand bag is 50 lbs , says it covers .5 cubic feet per bag. How many bags do I need?Answered by Penny Nom.

4 carpenters can build 8 houses in 10 days. 2 carpenters can build how many houses in 15 days?

Here is one solution:

The number of houses built is jointly proportional to the number of carpenters and the number of days. So h = kcd where k is a constant. Substituting the given: 8 = k*40, so k = 1/5. Our formula is then h = cd/5. I'm not sure how to determine whether or not one unit is jointly proportional to any other unit.

However, if 2 carpenters are unknown as in 4 carpenters can build 8 houses in 10 days. How many carpenters can build 6 houses in 15 days? What is the solution using this method? And likewise, if days are unknown, as in 4 carpenters can build 8 houses in 10 days. 2 carpenters can build 6 houses in how many days?

From Andrew:Suppose you own a local pizza restaurant, Pizza with Pizzazz, and in order to compete with the big pizza chains in your area you are considering an advertising campaign offering customers a free pizza if their pizza is not delivered in 30 minutes or less. Even though your pizza restaurant is known for its fast and friendly delivery service, you are not sure if you can afford to give away too many pizzas for free. Looking over your past 12,421 pizza deliveries you find out 97% of the pizzas were delivered in 30 minutes or less.

Calculate the probability that all 100 randomly selected pizza deliveries will have been made in 30 minutes or less? Hint: Use the multiplication rule. (Round 4 decimals)

I'm really stumped on how exactly to do this problem. I don't need the answer just the steps broken down to show me how to get it!
It would be gladly appreciated if you could help!Answered by Penny Nom.

From yousef:A man wishes to enclose two separate lots with 300m of fencing. One lot is a square and the other a rectangle whose length is twice its width. Find the dimensions of each lot if the total area is to be a minimum.Answered by Penny Nom.

From Mussharat:I have 20 mangoes and have to put them in 5 boxes such that
the numbers will be odd numbers.Also I can't cut or take the seed
out from the mango . What should I do. It's really confusing.
I'll be more than happy if you could help me.Answered by Penny Nom.

From Astri:I have a problem determining the fluid level for tilted cylinder tank.
Actually I've found some solution here for horizontal cylinder tank. What if the cylinder
is tilted at a certain degree, for example 30 degree from the vertical axis.
Thank you.Answered by Penny Nom.

From Pratyasha:A quadratic polynomial when divide by x+2 leaves a remainder of 1 and when divided by x-1 leaves a remainder of 4. What will be the remainder if it is divided by (x+2)(x-1)?Answered by Penny Nom.

From Caroline:I couldn't find a similar question, hopefully there isn't one!

I have a softball team of 18 people (7 girls and 11 boys), but am limiting each game to 13 players (6 girls and 7 boys). The season is 10 games long. How do I create a rotating schedule which allows members to play evenly? I tried separating the boys and girls to create rotation for each but I got confused. Some are unable to attend all games but for the simplicity of a rotation schedule can you please help?Answered by Robert Dawson and Victoria West.

From alondra:Ricky went on a bike ride. After 6 miles he got a flat tire and had to jog home. He jogs 3mph slower than he bikes, so the jog took 1 hour longer than the bike ride. At what rate did he travel each way?Answered by Penny Nom.

From Linda:Noel correctly adds the length of three sides of a rectangle and gets 88 cm her brother Ryan correctly adds the lengths of three sides of the same rectangle and gets 80cm. What is the number of cm in the perimeter of the rectangleAnswered by Penny Nom.

From Robert:I have a wall 40 ft. long and 4 ft. tall as well as another one that is 30 ft by 3.5 ft. tall that I am trying to build. how many 6 inch by 12 inch landscaping blocks do I need?Answered by Penny Nom.

From Rahul:How to solve definite integral of a sum. The specific problem is as follows,
Integral of ( 1+ sum of x^k, k=1 to k=n), x=0 to x=b *dx.
The answer is b + sum of b^(k)/k, k=2, to k=n+1. I understand only the integral
of first term. But integral of the sum I do not understand at all.Answered by Penny Nom.

From Peter:hi, i know that if i use a compass to draw a circle, i can use the same setting to mark 6 intervals along the circle circumference, how would i go about marking out 21 equally spaced points around the circumference?

if there an online calculator i can us, or some other interesting trick?

From Lucas:The area of a rectangle is given by A=x2+18x+72
-use factoring to find an expression for the dimensions of the rectangle.
-if the area of the rectangle is 7 square feet, what are the possible values of x?
-what are the dimensions of a rectangle?Answered by Penny Nom.

From Pauline:A woman measures the height of her child at birth and at monthly intervals afterwards.The child's height increases by 5% per month. Find the number of measurements she has made before the child's height is twice what it was at birthAnswered by Penny Nom.

From Steve:On your website, I was reading a question and your response from a girl named Angela in which you provided a formula by which her father, a welder, could figure out points on an arc corresponding to equal 3' intervals on a 30' chord where the vertex was 1' off the chord. Is there an equivalent formula when working with an ellipse? I suspect this change will make the calculations significantly more complex. I am building a deck that is half an oval, and would like to be able to mark out the perimeter by measuring the distance from regular intervals on the primary access to a corresponding point on the perimeter. I will then connect the points on the perimeter and cut a reasonably smooth arc. The length of the primary access will be 22' and width of the deck at the vertex is 9'. I would like to be able to know the distance from the primary axis to a point on the perimeter at equal intervals of 6" along the primary axis. Can you help?Answered by Penny Nom.

From percy:a regular polygon has n sides .The size of each interior angle is eight times the size of each exterior angle .
1.find the size of each exterior angle
2.calculate the value of nAnswered by Penny Nom.

From Thys:Hi
I have a problem with the formula that i use .(for programming)
I have looked all over the web to find a solution but no luck.
I have a cannon that shoots a ball at a target
I use this formula to calculate what my initial velocity must be to hit the target
at a angle of 30 degrees and a distance of 15m (the cannon and target position is known)
It works perfectly if both is at same height but if one is higher or lower it miss.

In an example I am working with the range is 30m, the angle is 45 degrees and the target is 10m higher than my position.
Please help
Formula = V0 = √RG / Sin(2α)Answered by Harley Weston.

From kechi:A boat sails south through Chesapeake Bay. It takes 10 hours to sail 110 kilometers. Describe the boat's motion. Calculate the boat's speed and velocity, showing the calculations. Explain how the boat's speed is different from its velocityAnswered by Penny Nom.

From Victoria:Todd is 3 years older than his brother Jack. If Jack is x years old and Todd is y years old, write a rule that relates their ages over time. When Jack is 28 years old, how old will Todd be?Answered by Penny Nom.

From Lloyd:A boat travelled 210 miles downstream and back. The trip downstream took 10hrs, the trip back took 70hrs
1. what is the speed of the current?
2. what is the speed of the boat in still water?Answered by Penny Nom.

From Jeremy:Hello, I'm going to be backfilling a rectangular hole for a shop foundation and need to know how much concrete and gravel I'm going to need to fill it in. The shop foundation is 38 feet wide by 30 feet long and 4 feet deep, there is also a concrete perimeter going inside the foundation that measures 16 inches wide and goes all the way around the inside of the foundationAnswered by Penny Nom.

From Carl:I am a welder and I build gates. I have to put holes in a rail and then bend the rail
in a curve. The problem is that the holes in the curved rail must line up with holes
in the other straight rails. How do I calculate where to put the holes in the rail
before I bend it? I will send a drawing if necessary.Answered by Harley Weston.

From Christian:Question: Two cars are racing to a fixed point and back. One car travels 70 MPH both ways
While the other travels 60 MPH there and 80 MPH back, which car won the race?
It is not a tie.Answered by Penny Nom.

From Andy:We are shortly having a golf holiday in Phoenix. There are 6 people playing 6 rounds, so we will play in 2 three balls. Is there a combination of pairings that ensures everyone plays with each other the same number of times. Many thanks for your help ! AndyAnswered by Victoria West.

From Kuuku:The daily production targets in 2000 was 60,000 units this declined to 48,000 units in 2001 but was projected that further 300units reduction would be experienced in 2002. Calculate the percentage reduction by 2002.Answered by Penny Nom.

From Kevin:Working on a project for a science fair.
To prove the earth is round without the ability to get way above the surface.
How could we set up and experiment to see the curve.
My thought is using a telescope at the beach?
Form what we see so far the curve is 8 inches per mile?
So thought is set up a telescope and a target 1 mile away?Answered by Robert Dawson and Chris Fisher.

From Subrahmanya:In a square ABCD of side 6 units P, Q are mid points of BC, CD respectively. The line segments BQ, DP intersect in R then find the area of the quadrilateral ABRD using only plane geometry.Answered by Chris Fisher.

From Z:How do I find how many books are in a library given a problem like this... The number of books increase after buying 20% more in May. The number increased again by 20% after they were given 300 books. How many books did it start with?.Answered by Penny Nom.

From Z:How do I find how many books are in a library given a problem like this... The number of books increase after buying 20% more in May. The number increased again by 20% after they were given 300 books. How many books did it start with?.Answered by Penny Nom.

From Peter:I am trying to calculate the diameter of a truncated cone given
one diameter the height of the cone and a 10% taper from one end
to the other. For example a butter churn is 18" tall and 9" in
diameter at the base. the sides need to slope inward at 10%
What is the diameter at 9" and 18"Answered by Penny Nom.

From Demetrie:Dwayne's garden is triangle-shaped with two equal sides and a third side that is 4 ft more than the length of an equal side. If the perimeter is 49 ft, how long is the longest side?Answered by Penny Nom.

From Tiffany:Khairul wants to buy a sofa set. He is offered 3 successsive discounts of 10%,20% and 25%, and he can arrange them in any order he wants. Which order will benefit him the most? Explain your answer.Answered by Penny Nom.

From Tiffany:the cross section of drain is a rectangle 30 cm wide. If water 3.5 cm deep flows through the drain at a rate of 22 cm/s, how many litres of water will flow through in one minute?Answered by Penny Nom.

From Brynleigh:The Sugar Sweet Company will choose from two companies to transport its sugar
to market. The first company charges $5096 to rent trucks plus an additional fee of
$200.75 for each ton of sugar. The second company charges $5500
to rent trucks plus an additional fee of $175.50 for each ton of sugar.
For what amount of sugar do the two companies charge the same?
What is the cost when the two companies charge the same?Answered by Penny Nom.

From sherica:my teacher gave us an assignment and it says here that;
THERE ARE FOUR CONSECUTIVE INTEGERS.IF THE SMALLEST ONE IS x ,FIND THE SUM OF THE FOUR INTEGERS. that is the question ...thanks hope that u can answer itAnswered by Penny Nom.

From Sandra:Your finance text book sold 56,500 copies in its first year. The publishing company expects the sales to grow at a rate of 20.0 percent for the next three years, and by 8.0 percent in the fourth year. Calculate the total number of copies that the publisher expects to sell in year 3 and 4.Answered by Penny Nom.

From Raj:Harris has an 87 in a class where daily works count 20%, quizzes count 20% and tests count 60%.
If there are only two test scores what must the score on his second test to raise his average to 90?Answered by Penny Nom.

From Ali:If I have an app and offer a two, three and four digits name and it can be only number, letters or both?
I want to know how many options will I have for each?
For example
the two digits: aa, 11, a1 or 1a
the three digits: 111, a2a, 222
the four digits: 1111, 2ge3 or 1234
So if I used all the letters and all the numbers but nothing starts with a zero
How can I calculate them separately? Or what's the result for each?
Thank you
AliAnswered by Penny Nom.

From Sharon:How do you turn a fraction into a percentage? I'm beyond confused with this. Even though I think of myself as a good math student doing 8th grade math at a young age, this just makes me want to scream! I get the way you turn 1/4 into 25%, but when it comes to something like 7/9 = ? I just can't figure out the answer.Answered by Penny Nom.

From Faith:Does the measure of angle determine the length of its side? For example two angles are congruent then the sides are also congruent because from my understanding the angle determine the shape of triangle.Answered by Penny Nom.

From Michelle:I do not know what equation(s) should be used in order to obtain the answer(s) to this word problem.

A bus was rented for a trip, the cost was dived equally amongst the passengers. During the trip, someone mentioned that if there were 9 more passengers, they would have paid each 5$ less. Another mentioned that if there were 6 less passengers, they would have each paid 5$ more. What is the cost of renting the bus and how much must each passenger pay.Answered by Penny Nom.

From Berteanu:I need help with this proposition:
"It exists x a real number that for every y real number 5*x-2*y*y=1
This is false.
Let x be from R.
And I need an y real number that 5*x-2*y*y!=1
Please,could you help me?Answered by Penny Nom.

From David:Retired math teacher trying to help son-in-law schedule a cross country district schedule. The would like to have four tri-meets each week for five weeks and one week of dual meets. The score the tri-meets as three duals, i.e. 1v2, 2v3, 1v3 constitutes one tri-meet. After many hours, not sure its possible, but I have forgotten a great deal! ThanksAnswered by Victoria West.

From Faye:I have been asked to build a dreamcatcher, which is round into a 3x3foot area. What would the circumference be that I would need to make the hoop? I am thinking it is 9.42 feet long but am not good in math.Answered by Penny Nom.

I would like to know if there is a particular equation to validate the following information:

I had to find the original cost of an item sold for 759.36$ before a 25% discount and 13% taxes.
I know we must use separate question to obtain the answer but I am unsure how to write the equation to validate my answer.Answered by Penny Nom.

From Jeff:We have 20 golfers playing a 20 week season. We play in foursomes. How best to set foursomes so everyone can play with every without playing with the same person multiple times?Answered by Victoria West.

From Roselyn:Jenny and Mark commute to work, travelling in opposite directions. Jenny leaves the house at 8 AM, and averages 35 kph. Mark leaves at 8:15 AM, and averages 40 kph.At what time will they be 40 kilometers apart?Answered by Penny Nom.

From J.H.:I am negotiating with a company to sell them land that they would use for excavating soil to be used in construction. I would like to value the land based on the volume of soil they are likely to remove. I have seen several answers, giving the calculation based on 43,650 sq. ft./acre x number of acres x number of feet in depth, divided by 27 to convert the number to cu. yds. However, that is the number when compacted. They pay $.50/yd. of soil removed, but that yd. is not compacted. How do you calculate the number of yds. of uncompacted soil in 1 acre of land?Answered by Harley Weston.

I have a league schedule question. We have a league where we have say have 15 teams. Each team is to play each other twice during a 10 week session.
However each team tries only to play 3 matches(teams) per night(week).
How would we set up a random schedule for the 10 week session?Answered by Victoria West.

From Jack:I need to build a truncated cone that has a top of30 inches and a base of 64 inches . The sides need to be at a 64.5 degree angle. This will determine the height. Can this be calculated?Answered by Penny Nom.

From sam:Michael, can climb a mountain at 2.5km/hr on his mountain bike. he descends the mountain at 5.5km/hr. he completes the whole circuit in 7 hours. how long is the trail to the top of the mountain?Answered by Penny Nom.

From Muhammad:An arch over a road has a parabolic shape it is 6 meter wide at the base and is just
tall enough to allow a truck 5 meter high and 4 meter wide to pass
a):
assuming that the arch has an equation of the form y=a(x)^2+b use the given
information to find a & b. explain why this assumption is reasonable.
b):
sketch the graph of arch equationAnswered by Penny Nom.

From Franc:a television camera is 30ft from the sideline of a basketball court 94 ft long. The camera is located 7 ft from the mid court. through what angle must it sweep in order to cover all action on the court?Answered by Penny Nom.

From Karan:I have been given an isosceles triangle. the Top angle is what i have to find out and the two sides adjacent to it are both 4.9 cm. i have been told that the area of the triangle is 4 cm^2. i have no idea how to work this out, any ideas?Answered by Penny Nom.

From Nazrul:f : R to R is a function which is defined by f(x)=(2x+2)/(x-1).
Is f(x) an onto function? Please explain.
What is the range of this function?
Thank you very much for your previous help.Answered by Harley Weston.

From Sean:Hi, I am trying to figure out how much the earth curves over a one foot distance. I'd like to be able to draw the exact arc on a piece of paper. I am an artist and am looking to make glass vessels with the exact curvature of the earth. I read on your site that it curves approximately 8 inches per mile. can I just use simple ratios to break it down into inches?? Thank you so much for your help.Answered by Harley Weston.

From Pam:Can you please help me so I can help my daughter the equation is the measure of angle v is 4 time the measure of its complement what is the measure of angle v when the equation is 4x+x=90Answered by Penny Nom.

From Ron:I have read about Archimedes and his work with sphere in cylinder and cone in cylinder and the volume relationships. Did he or any others also extend this to regular based polygon based regular like pillars, and columns? The ratio of 1/3 to 1 whole holds true with all regular based columns as example: a regular pyramid having a regular hexagon base inside a regular hexagon column of equal height.Answered by Chris Fisher.

I need this because i want to find the equation of Beloch fold. (Huzita - Hatori 6th axiom)
However if you know any other method to find Beloch folds equation, I am open for any suggestions.Answered by Chris Fisher.

From Jason:I have 12 high school golf teams (A - L). There will be 4 games each week for 4 weeks. For each game, 3 teams play at a time (A vs B vs C). I would like it where no team plays the same team twice. Week four is my issue as I seem to always have a team or two playing the same team again. Is it possible to have each team play each other only once?Answered by Victoria West.

From Tina:The sum of the digits of a 3-digit odd number is 13. The digit in the tens place is 4 less than the digit in the hundreds place and 3 more than the ones digit. What is the number?Answered by Penny Nom.

From James:The first formula for figuring cubic yards of concrete need is length in feet, times width in feet, times depth in actual inches, divided by 320. Such as, 150x 50 feet x 4inches divided by 320 = cubic yards. How and why does this formula work?Answered by Penny Nom.

From Karstin:The exterior of a concrete container will be 10 feet by 8 feet by 4 feet tall. The walls and the bottom are 6 inches thick. What will it cost to construct it if concrete is $98.95/cubic yard?Answered by Penny Nom.

From Darlene:Question from Darlene, a parent:
A farmer has 10,000 meters of fencing to use to create a rectangular field. He
plans on using some of the fencing to divide the rectangular field into two
plots of land by constructing a fence inside the rectangle that is parallel to one
of the sides. Let X be the width of the rectangular field. Write an equation
to express the area of the field as a function of X. Find the value of X that
maximizes the area of the field.Answered by Penny Nom.

Good Day.
I have to figure out the square footage of a quonset style roof that's not playing by the rules The building dimensions (rectangular) are 63'x135' the height of the roof is 9.25'. It not an entire Quonset, It's that style of roof,(curved). There are concrete block walls 10' up to the metal roof.

From Jason:Hi,
I can't seem to open my locker cause I forgot the combination, the numbers are 1-8
Without repeat for 4 number for example 1234 or 2345 for numbers 1-8 without any repeat.Answered by Harley Weston.

From Ged:Hope you can help with the following to save next years arguments !
Schedule for 8 golfers playing as pairs in 2 X 4 balls on 5 days.
No player to pair same player more than once and to have played with each player
In the 4 ball.
Thanks.Answered by Victoria West.

From Mariam:A pamphlet has the following dimensions: 4 cm by 6 cm
If the area of the pamphlet is doubled, what will be the length of each side if sides can be integer values only?Answered by Penny Nom.

From Joseph:We have a 15 team tournament. Each team plays all other teams. We need a schedule were each game has a work team. Thus at each fields we have two teams playing and one working. All teams need to play each other and also be a work team. Any help would be appreciated!!Answered by Victoria West.

From Janice:We have an eight team league that play at four time slots each week. It's a seven week season. How do we schedule so that each teams plays each other at least once?Answered by Victoria West.

From Allison:It ask me to find an example of an irrational number less than -5 and I don't
understand what the difference from a rational number and an irrational
number besides the fact that a rational number can be repeated and shown in
a simple fraction and an irrational number can't be written in a simple
fraction.
Can you help me?Answered by Penny Nom.

From Hazel:I have to make a schedule for my pool league. I have twenty teams each of which must play all other teams. I have ten tables which must also be rotated to all teams play on all tables.Answered by Victoria West.

From Adi:Hi!
Can you help me with a nagging problem, I searched a lot over the web and couldn't find it.
I saw this site I gave it a try and I found it to my liking.

I am confused how to subtract bases from other bases:
567 (in base 8)
- 456 (in base 8)
______________
?????????
How do you do this? I do know how to carry and subtract with different bases. Can
you please help me?

From Tyler:I'm scheduling a social curling league where all skips will play with all thirds, all seconds, all leads. And all thirds will do the same and so on. We have 6 teams of 4 and will be doing 6 rotations. Is it possible that all skips will play with all other players from other positions without anyone doubling up?
My initial thoughts were (1,1,1,1) (2,2,2,2) (3,3,3,3) (4,4,4,4)(5,5,5,5)(6,6,6,6)... then rotate the thirds up and seconds down but don't know what to do with the leads and even with just 3 positions there's doubling (1,2,6,x)(2,3,5,x)(3,4,4,x)...4s have doubled (4,5,3,x)(5,6,2,x)(6,1,6,x) as you can see I'm having problems
If you could let me know if this is even possible it would be greatly appreciatedAnswered by Victoria West.

From Anthony:im trying to make a game scheduled for 6 teams using a 1vs2vs3 ; 4vs5vs6 format.
all 6 teams randomly arranged in groups of 3. each team will play all teams at least twice, im trying to see how to make the number of times each team play another the same.
schedule should be arranged as such 1vs2vs3 4vs5vs6 so that (1vs2, 1vs3, 2vs3) and (4vs5, 4vs6, 5vs6)
i am limited to having only 2 sets of 3 at a time with 6 teams.Answered by Victoria West.

From Dean:I need an 8 team schedule for 2 time slots where 3 teams are on the ice per slot. I understand that there will be 2 teams on a bye per day. How do make sure that the byes are fair? Can you help me out?Answered by Victoria West.

From Kelly:Hi there. Some of your posts are close, but my problem is evening out the home
and away games. We have 6 teams in our league and we are going to play a 20
game schedule, playing everyone 4 times. We will play Fridays and Saturdays,
each weekend. Of course the ideal would be to have each team have a home and
an away game each weekend, but I realize that is impossible, but I would like it as
close as possible. Any help would be much appreciated!! We also were considering
opening with a home and away - Friday then Saturday with the same teams. Then
carrying on with playing everyone else and then possibly finishing up with the same
home and homeAnswered by Victoria West.

From Chris:In my first math problem, I found out that 100 cows will produce 21900 ft3 of waste over a year. However I don't know how to do the second part. How many acres of land would a farmer need to spread the waste on if he wanted it to be more that 6 inches deep? Thank you.Answered by Penny Nom.

From Aidan:I have six teams that will be playing five games.
I want each team to play each game once and each team to play each other team once.
Is this possible or should I add an extra round and let some teams play each other twice?Answered by Victoria West.

From Paul:I'm trying to set up a game matrix for my kids that will have 4 games in 4 time slots with 8 teams. And every team is playing a different game in a different time slot. I provided the initial matrix and I am trying to ensure that no 2 teams play each other more than once. That's my problem.
8 pm 9 pm 10 pm 11 pm
Crokinole 1 vs 2
Trivial Pursuit 3 vs 4
Darts 5 vs 6
Pictionary 7 vs 8
Please help, I've been at it for hours.Answered by Robert Dawson and Victoria West.

From Ellen:I will have 16 teams. I would like to figure out how I can have 4 groups of 4 teams playing in hour increments, but never meeting more than once. How do I accomplish this? Thank you so much for any help you can give to me. .Answered by Victoria West.

From Mike:We are six golfers going away for 3 days golf. We are playing in 2 no threeballs playing concurrently. How can we arrange things so that everyone plays averydody else at least once. Is this possible.?Answered by Victoria West.

Wondering if there is a way to figure out the quadratic equation of half of a parabola?
Doing an assignment about finding quadratic equations for separate bounces of a ping pong ball, but the first bounce is incomplete (as the ball has presumably been dropped, hit the ground and then went on to make a complete bounce).
Please see attachment for references to the diagram that I am using.

Not sure whether I would have to look at it from a different perspective.

From Lynn:I have 2 lots that have mobile homes on them... I was told they were 100 x 200 lots.. I have tried to calculate it on here but was not able to understand how to exactly do it. I would like to know if I have a 1/2 acreage or exactly what the 2 lots are?Answered by Penny Nom.

From anagha:Hi,
thank you for answering (beforehand)
The other day I was just thinking of circles and I came across this peculiar thing.
Most of'em say that there are infinite number of points on the circumference.
and, if it is true, if we spin the radius, the probability that it will point a a particular point is 1/infinity, right?
It didn't make any sense to me and so, I thought there might be an explanation or something of the kind...?Answered by Harley Weston.

From anagha:Hi,
thank you for answering (beforehand)
The other day I was just thinking of circles and I came across this peculiar thing.
Most of'em say that there are infinite number of points on the circumference.
and, if it is true, if we spin the radius, the probability that it will point a a particular point is 1/infinity, right?
It didn't make any sense to me and so, I thought there might be an explanation or something of the kind...?Answered by Harley Weston.

From Brian:We have a hockey roster of 19 kids. We only want to play 15 kids for each game. 4 players will not play each game. There are 16 games total. We want to rotate who doesn't play evenly. Can this be done? How many games will each player sit during the season?Answered by Robert Dawson and Victoria West.

From mariana:I have read various articles on how to find the square root of irrational numbers and every article out there seems to be very confusing.
i read you answer to LUKOW about irrational numbers and i am still quite confused. Say i want to find the square root of 326. i know that it is between 18 and 19 because 18 is the square root of 324 and 19 is the square root of 361 im just very confused about the rest of the process. Please help! ( if possible i would appreciate two examples. thanks)Answered by Penny Nom.

From Brian:Looking for a formula where I can type in a number, 17 for example, and using the numbers 1 through 17 (1, 2, 3, 4 etc....), to come up with all possible combinations, when added, that will equal 17. And each number can only be used once. I've tried a few search engines but my computer stares at me blankly and scratches its head :-/.Answered by Chris Fisher.

From Suszanne:Mary purchased an item for 45% off the original price, plus an additional 20% off the sale price.She also had a $5 off coupon, which the salesclerk applied after these two discounts. Mary's final purchase price for the item was $50. She paid no sales tax, what was the original price of the item?Answered by Penny Nom.

From jeff:We are trying to solve a combination problem. If I have 7 things that can be in 3 states (say on/partially on/off), and all 7 have to a state. How many different combinations can there be? It doesn't seem like we should treat it as 21 independent things, but not sure how to break the problem apart.Answered by Penny Nom.

From Tanisha:I would just like to double check if something like 5x squared times 4x cubed equals 20x to the power of 5??
It's just that we were told you can only answer an equation like this if the base is the same...so does that mean the x part or the whole thing like 5x?
I'm sorry if that didn't make sense!

From Dave:have 20 golfers for 6 days. Each player should pair with 18 golfers
used a system on your website which is good for 5 days, but cannot get the 6th day.
Thanks for your help DaveAnswered by Victoria West.

From Paul:I have 18 golfers playing four rounds. I want two 3 balls and
three 4 balls each day. I don't want anyone to play in a 3 ball
more than once and I don't want anyone to play with the same
person twice. I realise everybody can't play with everybody, I
just want the best you can do.Answered by Victoria West.

From margot:Can you help me with scheduling our bridge club?
8 rounds are played with four teams together.
There are 16 teams in total, so our schedule should look like eight 4x4 boxes.
(Each round the four teams play each other over the course of the evening)Answered by Victoria West.

From Joel:We are having a youth activity where we have eight teams and four stations. At each station there will be two teams competing against each other. We need each team to go through all four stations, but without ever competing against the same team, and, of course, without ever doing the same station twice.

From Tracey:Hello,
I own a custom workroom, I am figuring out fabric quantities or an estimate. When
at the job site, I forgot to measure the diameter of the semi circle shape that I have to
make a cushion for!!!
If the circumference of the semi circle is 165" what would the diameter be, maybe half
this measurement????

I appreciate any help...I basically need the width from left to right to see if I can fit
the cushion on one width of fabric that is 52" wide!Answered by Penny Nom.

From Shelly:My son brought home a problem of 3 chickens of different weights listing their weights in different groupings of 2. We are to determine the weight of all three together. I think it's a ratio problem, but I am too far removed to formulate a plan to teach him how to solve it.Answered by Robert Dawson and Penny Nom.

From Faustina.:Please I have an exam tomorrow. And I have tried by best in solving this Question. An urn contains 10 white, 5 yellow and 10 black marble. A marble is chosen at random from the urn and it is noted that it is one of the black marble, what is the probability that it is yellow?Answered by Penny Nom.

From Padmesh:in a circular foundation we are laying a reinforced steel mesh . i.e., like chords in both ways. the circle diameter is 2.91m and rods are placed 0.1m spacing. so I want to find the number of rods present in that circle. here by I am attaching an auto cad drawing for your referenceAnswered by Penny Nom.

From Paul:I have a party of 20 golfers playing four rounds in fourballs.
I realise that everyone will have 7 players that they do not play
with, however I want to ensure that no one plays with the same
person twice and that the Captain plays with the 12 players of
his choice.Answered by Victoria West.

From Nigel:To find the area of a parallelogram you multiply the base by the height of the parallogram, the height being determined by an imaginary line drawn at right angles to the base. However if I made a parallelogram with joints at each corner and maipulated it to an upright position where the base and sides were at 90 degrees to each other,, I could then simply multiply the base times the height to get the area. Since the sloping side of the parallelogram does not vary in my imaginary jointed model, why can I not simply multiply the base by the sloping side to get the area in the same way that I multiply the base times the height of a square to find its area ? I cannot find the answer to this on the internet although I have searched.Answered by Chris Fisher.

From Michael:I have a storage tank that is 12' diameter x 22.5' high
it's capacity is 450 oil field barrels (42 gallon)
Which would hold 19,036 us gallons
I'm trying to find out how many inches it would take to make 1 barrel
I was able to get this far by using your volume calculator, but haven't been able to come up with the rest!
Thank you very much for your time, and I really appreciate this site and the tools you all have made available to everyone for free!
Hope to hear back from you soon and God bless you all!!Answered by Penny Nom.

Lizzie, who is 6 feet tall, stands in her driveway at night, exactly
24 feet from the base of a spotlight, and casts a shadow that is 12
feet long if her friend Hannah who is 5 feet tall decides to stand
next to lizzie how long will her shadow be?Answered by Penny Nom.

From Ken:I hope you can help me. I'm trying to put together a draw for 12 players in 3 groups over 4 days. One proviso, 2 players must play together in each round because they require the use of a golf cart. We are due to play in September this year.
Thanking you in advance for any assistance you can give.Answered by Victoria West.

I got 1 as my answer despite BODMAS making it 12 because logic tells
me I ought to place brackets around the first set of repeated addition. Could you
please clarify this for me? Thank you 😊Answered by Harley Weston.

From Gary:What is the number of possible combinations using the following fact pattern?
A. Each combination must have 4 numbers.
B. The possible numbers to choose from are 1, 2, 3, 4
C. The numbers can be included in the combination more than once. For example, it can be 1111.

Is it possible to generate a schedule of the possibilities?Answered by Penny Nom.

From Angela:a waste oil tank is 5 feet wide and 20 feet long, the empty tank on your truck holds 5000 gallons. If 7.48 gallons are in every cubic foot, what is the maximum depth the oil can be to completely fit into your truck?Answered by Penny Nom.

From kelly:I have an existing amount of $22,750.00. this includes the profit at 10% and overhead at 10%.
How do I remove the profit and overhead in order to come up with the original starting figure?Answered by Penny Nom.

From Jason:Hello. We have a fantasy football league with 14 teams. The season is 13 weeks long and we would like to figure out a way to have two divisions of seven teams each with each team playing their inter-division opponents twice. Is there a way to set this up? I cannot seem to find a way to do it. Thanks!Answered by Victoria West.

From Casey:I have an equilateral triangle inscribed in a circle - this triangle
has been bisected to give me 2 right triangles. I know the length
of the line bisecting the equilateral triangle is 36 inches. How do
I figure out the circumference of the circle and the length of the
sides of the equilateral triangle?Answered by Penny Nom.

From Madison:Trini took some photos. The number of photos she took is a two digit number.
The sum of the digits is 11. The tens digit is 3 more than the ones digit.
How many photos did Trini take?Answered by Penny Nom.

From Brayden:Show that a tangent line drawn to the curve y=x^3 at the point (d,f (d)), where d>0, forms a right triangle with the x and y axes in quadrant 4 whose area is (2/3)d^4.Answered by Penny Nom.

From Imran:The length of a rectangle is x+3 centimetres.
The width of the rectangle is x-1 centimetres.

Find an expression in terms of x for the perimeter of the rectangle.
The perimeter of a rectangle The perimeter of a rectangle
Give your expressions in it's simplest form.
The perimeter of a rectangle The perimeter of a rectangle
Thank You.Answered by Penny Nom.

From Katie:Solve x=At^be^-ct for b in terms of c.
The e is Euler's number, not a letter or random placeholder.v
I've tried 2 methods on my calculator, and I am unsure as to why they give me different answers, and which one is correct.
For some reason, when placing a multiplication sign in between the A and the first t, I get a completely different answer. Why is this?
Also, which is the right answer for the question I have?
Thank you!
Katie :)Answered by Penny Nom.

From Tom:Is there a way to derive an equation that describes the perimeter of the intersection of a plane and a cone regardless of the angle of the plane to the cone. Assume that the plane does not cut through the base of the cone, the x, y, z location of the vertex is known, the distance from the vertex to the plane through the axis is know., and that the angle of the cone is known.Answered by Chris Fisher.

From Justin:I have a pile of mulch that measures 19 feet wide at the bottom and has a height of 6 feet. I need to know how many yards of mulch I have.
Please help and help with the formula for further use. Thank you!Answered by Penny Nom.

From Nuraini:Two straight roads intersect at the right angles. Lorry A, moving on one of the roads,
Approaches the intersection at 50mi/h and lorry B, moving on the other roads, approaches the intersection at 20mi/h.
At what rate is the distance between the lorry changing when A is 0.4 mile from the intersection and B is 0.3 mile from the intersection?Answered by Penny Nom.

From Ali:Given an elliptical piece of cardboard defined by (x^2)/4 + (y^2)/4 = 1. How much of the cardboard is wasted after the largest rectangle (that can be inscribed inside the ellipse) is cut out?Answered by Robert Dawson.

From Anna:If you fold a rectangular piece of paper in half and the resulting rectangles have the same aspect ratio as the original rectangle, then what is the aspect ratio of the rectangles?Answered by Penny Nom.

From Vir:Years ago I (re?)discovered 'cyclic division'. For example: if you arrange the number along a circle and put the number 142857 at the centre
all the numbers taken cyclically, starting with 1, are fully divisible by 37. Whatever the starting point of this number, it remains fully divisible by 37.
what is more, the number can be formed by taking the digits clockwise as well as anti-clockwise..This I call "full cyclic divisibility". In many cases, only clockwise cyclic divisibility is possible. But I have not come across a case where ONLY anti-clockwise divisibility occurs. Thus clockwise cyclic divisibility seems to be favoured. Could this be construed as a sign of chirality in mathematics?..Answered by Chris Fisher.

From JAMES:A businessman bought a number of similar articles for a total of sh. 6000. Three of the articles turned out to be defective with no resale value. He sold the remaining articles at 12.5% each above the cost price making a total profit of sh 480. How many articles had he bought?Answered by Penny Nom.

From Adalyn:Hello i've been having some trouble with math, The question is asking for a GST
and a PST
of a 30.00 dollar shirt. I don't know how to find the GST or the PST please helpAnswered by Penny Nom.

From Farihin:Lets say that i have keys, and each key is for notes of a musical instrument,
So i wanted to find out the number of notes i can get for a certain number keys,
of course in the form of an equation. Notes can use as many keys, it can use 1, or 2, or 3, or even 100.
Notes in real life is not as such, but ignore reality.
I tried doing this but i can't seem to find a formula for it.
For example, i have 4 keys, say A, B, C, and D.
so, for notes that uses one key are 4, which is A, B, C, and D themselves.
for notes that uses two keys are 6,
AB, AC, AD, BC, BD and CD.
for notes that uses three keys are 4,
ABC, ABD, ACD and BCD.
lastly for notes that uses all four keys is 1, ABCD.
So, the total will be 4+6+4+1=15#

The nth term for the first equation is n, the second is [(n^2)-n]/2
the third and the fourth, i don't know but the final answer should be like,
n + [(n^2)-n]/2 + [3rd] + [4th]

From Kennedy:Hello, hope it finds you well.
Am not that good with numbers, can you please help me get all the possible outcomes of 13 games, with a home win, draw or an away win as three possible results for each of the 13 games.

From Mike:I have a hole which a 24 ft pool in it is 10" deep in the the centre and goes to 1" inch at the edge want to fill it in with dirt how many yards of dirt would I need to fill it inAnswered by Penny Nom.

I have the same type of lock, but set up a 5-digit pass code. Is that more or fewer possibilities than a 4-digit code. How many digits would make the lock most secure? I don't believe Werner specified this, but each number can only be used once. Thanks, Mary

Find the Cartesian coordinates of the center of an arc with the given location of the beginning and end points and radius length. Not the midpoint of the circumference but the actual point that the arc
is drawn around.

I know their are two answers depending on the direction of the arc. Unless we assume that all arcs are drawn counter clock wise.

From Juniper:Two concentric circles have radii of 4 cm and 8 cm. A segment is drawn so that it is tangent to the smaller circle and a chord of the larger circle. How long is the segment?Answered by Penny Nom.

From Engabu:Car A is traveling west at 50km/h & car B is traveling north at 60km/h. both are headed for the intersection of the two roads. At what rate are the cars approaching each other when car A is 3km & car B is 4km from the intersection?Answered by Penny Nom.

From Carla:In a marina, 3/4 of the boats are white, of the remainder 4/7 are blue, the rest are red. There are 9 red boats. How many boats total are in the marina? My answer is 84 because if 1/4 of the boats are divided into sevenths, that makes the whole marina a 28 part item. 3/28 are red so 84 is the total number of boats. My child thinks I am wrong.Answered by Penny Nom.

From john:two planes leave an airport at the same time, one going northwest (N35*W)at 400 mph and the other going east at 332 mph. How far apart are the planes after 4 hours to the nearest mile?Answered by Penny Nom.

From Margot:I need to do a PA for maths and I'm a bit stuck.
The PA is about folding a box with a volume that is as big as possible. The first few questions where really easy but then this one came up.

8. Prove by differentiating that the formula at 7 does indeed give you the maximum volume for each value of z.Answered by Penny Nom.

From Rachel:Triangle ABC is an isosceles triangle inscribed in circle O. If each leg of the triangle is 13cm and the altitude to the base of triangle ABC is 5cm, find the radius of the circle.Answered by Penny Nom.

From Ngcebo:A train travels a distance of 720 km at a speed of x km/h. on the return journey, it travels at an average speed of y km/h and completes the whole journey in an hour less. if the speed during the return journey was 10 km/h more, what were the speeds in m/sAnswered by Penny Nom.

From Rose:We could use a schedule to include the following:
16 golfers
4 foursomes
Each person plays once a week for 18 weeks.
No one plays in same foursome more than 1 or 2 times, or the least
amount of time.

From Mary:I have to use a 8 1/2 inch by 11 inch piece of paper to make a cone that will hold the maximum amount of ice cream possible by only filling it to the top of the cone. I am then supposed to write a function for the volume of my cone and use my graphing calculator to determine the radius and height of the circle. I am so confused, and other than being able to cut the paper into the circle, I do not know where to start. Thank you for your help! -MaryAnswered by Robert Dawson.

From Justin:jamie tells her friend that ordered pairs that have an x-coordinate of O line x-axis. She used the origin as an example. Describe Janine error. Use a counterexample to explain why Janine statement is falseAnswered by Penny Nom.

From Ruby:This question showed up in one of my Math assignments and nothing on the internet seemed to help me find a way to calculate it.

A certain country has a two-tiered GST system. For the first $1500 of any item, GST is levied at 10% and any amount over $1500 is levied at 15%.
Determine the amounts that give the following GSTs.
a) $350
b) $780Answered by Penny Nom.

From Michael:Jeffrey drove to a town 25 miles away at an average speed of 50 miles per hour. The return trip along the same route took 20 minutes longer than the trip to town. Determine the average speed in miles per hour for Jeffrey's round trip.Answered by Penny Nom.

From Rose:A shopkeeper receives 12.5% (12 1/2 %) commission on the sale of books from
the publisher. In a certain month,he receives a commission of rs.250 from the
publisher. How much was his sale for that particular month??Answered by Penny Nom.

From Dave:I have a fishfinder that has a 20 degree cone on bottom of boat going to the bottom of the lake.
How do I know the size of base diameter of the cone on the lake bottom depending on depth...
such as 10 feet deep, for example?Answered by Penny Nom.

From Rebeccah:Olivia and Ray walk to school. Olivia walks 1/4 of a mile to school. Her walk is 2/3 of the distance that walks Ray to school. What is the total distance,in miles,that Ray walks to school?Answered by Penny Nom.

From Maurice:Sam and sally planted two sunflowers.Each sunflower grows 1cm each day. Sally's sunflower is 4cm high. Sam's is 12cm high. How high will each sunflower be when Sam's sunflower is twice the height of Sally's?Answered by Penny Nom.

From Levi:While the mathematics at the welding shop page was very helpful there is one vital part missing. If I have never built a cone how do I figure out how much bigger the diameter of my
circle has to be when laying flat on the floor verses the diameter when it has been pulled into a cone.Answered by Harley Weston.

From Joel:Diagonal ac of quadrilateral ABCD is 60cm and the lengths of perpendiculars to
It from the opposite vertices are 4.2cm and 5.8 cm find the area of the quadrilateral
ABCDAnswered by Penny Nom.

From Timmy:Joel is walking down a street and sees a 115 ft tall building in front of him. He stops 190 feet from the base of the building at the tip of the building's shadow. Round answers to three decimal places.

A. If there was a piece of rope from the top of the building to Joel, how long would it be?
B. What is the angle of elevation from Joel to the top of the building?
C. Margaret says that she could find the angle of depression from the top of the building to Joel by subtracting the angle of elevation from 90°. Is she correct? Explain.Answered by Penny Nom.

From Emily:I have a question about Extraneous Solutions, Because I was recently researching to figure out
on how to determine that a solution is extraneous and many of the answers talked about how if a answer is negative
that it should always be extraneous but now I found out that positive solutions can also be considered as extraneous solutions
so that is why I am really confused Extraneous Solution's.
I would really appreciate it if you could clearly explain to me how to determine an extraneous solution from a normal solution.
Thanks,
EmilyAnswered by Chris Fisher.

I saw this definition online from the Free Dictionary (The Free Dictionary.com) regarding the definition of percent (%):

"Noun 1. a percent sign - a sign (`%') used to indicate that the number preceding it should be understood as a proportion multiplied by 100."

What is this "proportion" multiplied by 100?

When I think of a proportion, I think of a/b = c/d. How can a number preceding the percent sign be understood as a proportion X 100?
I thank you for your reply!Answered by Chris Fisher and Claude Tardif.

From ana:Julie lives on a cul-de-sac and wants to know if the city calculated the area of her plot of land correctly (see diagram below). We can assume the cul-de-sac is a circle and it has radius 40 feet.The boundary of the lot along the cul-de-sac (the arc from A to B) is 78.21 feet. The city found the area to be 7012.5 square feet–are they correct?Answered by Penny Nom.

From kiki:a man of height 1.5m standing on top of a building of height 48.5m views another building across the square. he observe that the angle of depression of the bottom of the building is 40 degrees and the angle of depression of the top of the building is 5 degrees. Both buildings stand on the same level
a) calculate the distance of the man from the base of the building across the square measured along the line of sightAnswered by Penny Nom.

From Jayson:I have a round fire pit. It measures 25 inches in diameter. I have 12 inch long square bricks to go around it . My question is what degree do I cut the ends of these bricks to make them fit around this circle? The brick dimensions are 12"Lx6"Wx4"D.Answered by Harley Weston.

From Victor:A plane flies from Istanbul to Lagos at 800km/h and then returns to Istanbul at 900km/h. The return trip takes 1 hour less than the flight to Lagos. What is the distance between Istanbul and Lagos?Answered by Penny Nom.

From Rose:Hi. I want to know how to find the radius of cylinder.
When I have height (35cm) and area of the curved surface(880sq.cm).
I know the formula is 2πr(h+r). But I can't understand how to find it's radius.
Please help me. I really need your help.Answered by Penny Nom.

From Manasi:The area between 2 concentric circles is 6 times the smaller circle. Radius of small circle is 7 cm. Find the difference in the circumference of the bigger circle ad the smaller circle?Answered by Penny Nom.

From Rahul:I am not able to visualize a solid given by inequalities as under (in cylindrical coordinate system)
0=
I know that (can visualize) first 2 inequalities say it is a cylinder of infinite length.
It seems that third inequality poses the restriction to the height as well as it makes us to remove a cone.
But I just can not understand it clearly.
Thanks in advance!
Regards,
RahulAnswered by Penny Nom.

From prateek:the height of a flagpole on top of a building is 6m.
the angle of elevation of the top and bottom of the flagpole are 45 and 30 respectively.
find the height of the buildingAnswered by Penny Nom.

From Sreeharsha:The diagram shows an isosceles triangle ABC in which BC = AC = 20 cm, and angle BAC = 0.7
radians. DC is an arc of a circle, centre A. Find, correct to 1 decimal place,
(i) the area of the shaded region, [4]
(ii) the perimeter of the shaded region. [4]Answered by Penny Nom.

From Mubashir:Steven left Town A and walked towards Town B at a speed of 100m/min. At the same time, Jason and Melvin started from Town B and walked towards Town A at a speed of 80m/min and 75m/min respectively. If Steven met Melvin six minutes after passing Jason, find the distance between Town A and Town B.Answered by Penny Nom.

From Mubashir:A,B,C,D are the four corners of a rectangular plot marked on level ground. Given that the bearing of B from A is 040 degrees and that the bearing of C from A is 090 degrees. Calculate the bearing of
(a)B from C
(b)A from C
(c) D from CAnswered by Penny Nom.

From Audrey:A Harley Davidson motor cycle weighing 650 lbs with a rider weighing 175 bs
was going 40 miles per hour. He had to make a sudden stop . Slammed on brakes. How long a distance for him to stop?Answered by Penny Nom.

From Caroline:Two cars pass each other going i opposite directions. One car is going 100 km/h and the other is going 80 km/h. How far apart will the two cars be after driving 45 minutes at these rates of speed?Answered by Penny Nom.

From Tea:Serena and Nina are taking a train from Vancouver to Whistler, a 160km trip. If the average speed is decreased by 16km/hr, the trip will be 1/2 hours longer. What is the average speed of the train?
Thanks :)Answered by Penny Nom.

From APRIL:Two vertical poles are 3 meters apart. Jack is climbing one pole while Jill climbs the other. If the distance between Jack and Jill is 5 meters, how much higher is Jill than John?Answered by Penny Nom.

From Chris:I would like to find the gas oil ratio for a 2 cycle engine.
I have the gallons of gas and the ounces of oil used by
the engine, but I want to find what the ratio is. For example
I used 5.675 gallons of gas and 5 ounces oil what is the ratio?
Please explain step by step, and I understand there are 128oz in
a gallon.Answered by Harley Weston.

From Hannan:Lake Utah has a surface area of 3,846 square miles and an average depth of 10.5 feet. In cubic miles, how much water does it hold?
How would you approach this question? Where would you start?Answered by Robert Dawson and Penny Nom.

From Fabian:Two observers on level ground position themselves 50 meters apart so that an obelisk is due north of position A and due west of position B. The angle of elevation to the top of the obelisk at position A and B is measured to be 29.9 degrees and 37.5 degrees respectively. Use this information to estimate the height of the obelisk.Answered by Penny Nom.

From Pramegh:In a motorbike race of 75 km, the winner completes the race with a lead of 300 meters and 8 seconds before the second rider. Considering the riders ride with an average speed, find the difference between their speeds with which they completed the race.
(Calculate up to 2 decimal places)Answered by Penny Nom.

From Mubashir:there are two curves y=sinx and y=cosx intersecting at point where x is less than 90 and greater than 0.to find the point I made a equation sinx=cosx
but donot know what to do further .please help me by solving this equation sinx=cosx
also tell me that have you solved this equation by reference to the graph or by other means please do elaborate your solution in your answer.Answered by Penny Nom.

From Jennifer:I am a sales trainer. Each month we need to observe one of our peers and give feedback. What this means is every month, not only am I observing someone, but someone is also observing me. For example, in January, Amy observes Tracy, Tracy observes Rachel, Rachel observes Ryan, and so on. The last person would then observe Amy, bringing it full circle. There are 10 trainers on my team. How do I set it up to where each trainer observes another trainer only once over the course of the year (and in return, each trainer is only being observed once by each person)? I know they will eventually repeat but would that start in the 10th month?Answered by Robert Dawson.

From Cynthia:We have 5 employees and need only 2 to work on Saturdays. what is the best
way to fairly schedule everyone. PS. from time to time a sixth person will be
thrown in to make things really interesting.Answered by Victoria West.

From Valence:Mary gave her sister 5/8 of her nuts. Her sister gave her friend 2/3 of the amount, and her cousin 1/3 of the remainder. If Mary's sister had 50 nuts left, how many nuts had Mary.Answered by Penny Nom.

From Jacey:I am trying to figure out a formula/system to pair up a list of people so they meet with each other every month, but they rotate who they meet with. Right now I have 13 people and I would like to just type in their names and then have the system put each person with someone else every month and rotate so no one gets the same person twice. Can this be done?Answered by Victoria West.

From kirara:Find the volume of water in a swimming pool with vertical ends and sides. The length measured at the water line is 50 ft. And the breadth is 20 ft. The bottom of the swimming pool is a plane sloping gradually downward so that the depth of the water at one end is 4 ft. And at the other end is 8 ft.Answered by Penny Nom.

From Emily:A man 2m high observes the angle of elevation to the top of the building to be 70 degrees. And the angle of depression to the bottom of the building to be 19 degrees. How tall is the building?Answered by Robert Dawson.

From taylor:two cars leave the park at the same time, one traveling north at a speed 10 mph faster than the other which is traveling south. after 3 hours the cars are 420 miles apart. find the speed of both carsAnswered by Penny Nom.

From patience:An empty tank for storing water from a borehole has a volume of 480 cubic metres. If it is filled by a pump that pumps water at a rate of 16 litres per second, how many hours will it take the pump to fill this tank please show all calculationsAnswered by Penny Nom.

From Jim:When using a scale e.g. 0-10, what is the formula for calculating percentage change. For example when someone answers a questionnaire where a question has a 0-10 scale, and they score a 4 first time, and then they answer the same questionnaire a different day, and they score an 8, how do I calculate the percentage change.Answered by Penny Nom.

From Kent:I have an item I sell for $19.95 and make a profit of $10.97 for each sale.
If I reduce the price to $14.97, my profit is $5.99 each sale.
Is there a formula to determine how many more I would need to sell
at $5.99 per sale to make the same net cash (profit) as selling at $10.97 per sale?Answered by Penny Nom.

From Janelle:I had a friend try and play a game on me, regarding phone numbers, so I only know the area code , and the last four digits of the phone number. Which means, there are 3 digits that I need to figure out all the possibilities to.Answered by Penny Nom.

From Sabrina:I have 12 staff members that need to have lunch together 1 time each week. I am trying to pair them in a way that we each have the same amount of lunches in the same amount of weeks. Please Help! Thanks!Answered by Victoria West.

From Nichole:How do I determine the degree of polynomials? I've searched this on sites but they are
all so confusing! Is there a simple explanation or way to find what the degree is? Some
examples are: 6x^4 10x^2yz^5 and 3m^2n^7-10m^8. I also have to say that I am
under the impression that this symbol ^ means the number after it is an exponent.Answered by Robert Dawson and Harley Weston.

From Ami:A silo is composed of a hemisphere and a cylinder. The total height for the silo is 20m and the diameter of the silo is 8m. What is the volume of the silo to the nearest cubic meter?Answered by Penny Nom.

From Mr:The cold tap can fill a bath in 5minutes,the hot tap in 15,and the waste pipe empty the full bath in 10 minutes. All three are fully open for 2 minutes,after which the waste-pipe is closed. How much longer will it take to fill the bath?Answered by Penny Nom.

From Jimmy:Both batteries died in my scientific calculator and I have lost my formula for the heigth of the curvature of the earth between two points on the surface. I used degrees and miles. I only had to enter the distance between the two points on the surface and the formula gave me the hieght the earth raised between the two points.Answered by Robert Dawson.

From Ekanem:QQ A motorist had planned to reach a place 196km in two hrs exactly. For the first 15km he was able to average only 40km/h. What average speed must he keep up for the rest of the journey if he is to arrive on time.Answered by Penny Nom.

From Lyn:I would like to know a formula that I would use on a standard calculator to calculate a 30% profit margin on an item.
If I purchased an item at $7.70 how would I calculate 30% profit for me, not just 30% mark up?Answered by Penny Nom.

From Joseph:I need the angles in degrees for a hexagon one side is 18inches on the outside the problem I am having is in the angle of the cut and I am using a sliding miter saw which only goes from0 degrees to 45 degrees so I need help in getting the angle of the cutAnswered by Harley Weston.

From Hannah:A designer vase has the shape of a truncated, square-based pyramid. The base of the vase is a square with a side length of 15 cm. The area of the square opening is 70.56 cm2. Each of the four sides is a trapezium with slant sides 9 cm long. Find (to the nearest square centimetre) the total surface
area of the vase.Answered by Penny Nom.

From Jordan:hi i saw a question in class today that i didn't understand and i didn't really understand what my teacher was going on about so how do you factorise 15x + 15yAnswered by Robert Dawson and Penny Nom.

From Laura:7. A ship leaves its home port and sails on a bearing of N28.17°E. Another ship leaves the same port at the same time and sails on a bearing of S61.83E. If the first ship sails at 24 mph and the second at 28 mph find the distance between the two ships after 4 hours.Answered by Robert Dawson.

From Cole:Susan and Russell are brother and sister. Susan says that in two years she will be twice Russell's current age. Russell says that he's only three years younger than Susan. How old is each of the siblings?Answered by Penny Nom.

From james:I have an irregular convex octagon, alternating between 4 large edges, say 'a' mm long and 4 small edges, say 'b' mm long, is there a formula available so that I can work out the minimum size sit a circle with a radius of 34.25mm inside it thank youAnswered by Chris Fisher.

From Christine:On a math test, it said "What is -3 squared?" It did NOT say "What's is (-3)squared"

The teacher's explanation is that if there are no brackets or parenthesis, you ALWAYS square the number first then do the negative, so the answer should be -9, but I can't find anywhere that confirms this.

From Gracie:i really need help with this problem in my math book, will you help?

"Derrick drew regular pentagon with side lengths of 8 centimeters.
He divided the pentagon into 5 identical triangles, and measured the
height of one of the triangles to be 5.5 centimeters. Find the area of
the pentagon."

this really makes no sense to me. Can you help me with anything
to make it easier?

From Sarah:How do you find the area of a circle if you already have the circumference?
There was one answer to this question already but it didn't make sense to
me, because they rounded up pi which you can't do so the answer is
incorrect. thanksAnswered by Penny Nom.

From Hannah:A flea jumps from the ground to a height of 30 cm and travels 15 cm horizontally from where it started. Suppose the origin is located at the point from which the flea jumped. Determine a quadratic function in vertex form to model the height of
the flea compared to the horizontal distance travelledAnswered by Penny Nom.

I need to find out the the density of sea sand to convert one metric ton to cubic
meter as I am submitting for a tender which is in cubic meter but the requirement
is in metric ton. I searched through the web site but no density of sea sand is given
though there is specific Gravity of dry sand is available. I was given a density of
1.6 to work with. If that is true am I right to say that 1 cubic meter of sea sand is
equivalent to 1.6 metric ton? Please help as I am getting confused with what I am
able to find out on the web.
Thanks much in advance
Rgds
LennyAnswered by Penny Nom.

From Adam:The current in a stream moves at a speed of 2 km/h. A boat travels 38 km upstream and 38 km downstream in a total time of 3 hr. What is the speed of the boat in still water?Answered by Penny Nom.

From khushboo:The zeroes of a quadratic polynomial x^2+ax+b are 'c' and 'd'
and the zeroes of a quadratic polynomial x^2+cx+d=0 are 'a' and 'b'.
find the numerical value of a+b+c+d where a, b, c and d are non zero integers.Answered by Penny Nom.

From Beth:How do you find the height of the original square-based pyramid when given the sides (12cm) of the base and height (6cm) of the truncated pyramid, as well as the sides (3cm) of the base of the chopped off top (chopped off parallel to the base)?Answered by Penny Nom.

From Natalie:A spherical container with radius 10cm being filled with water such that the water level, h cm, in the container increase at a rate of 0.5 cm s^(-1). Show that the area of the horizontal surface of water, A cm^(2), in the container is given by A = π(20h - h^(2) ).Answered by Penny Nom.

From Marjorie:How do I figure out the following? Dylan's dog weights 12 times more than his pet rabbit. The dog and the rabbit weight 104 pounds. How much does Dylan's dog weigh? Would you explain in detail how I would arrive at the answer so I can convey same to my grandson who is in the 5th grade.
Thanks.Answered by Penny Nom.

From Michael:I want to build an 8 sided box. The North, East, South, and West sides I want them to be 4 feet in length.
The NE, SE, SW, and NW sides I want to be 2 feet in length. What angles do I need to cut my angles.
Thanks MichaelAnswered by Penny Nom.

From junna:a farmer would like to plant trees on one side
of his lot which is 1/4 of a mile in a length
His friend advised him that if he would plant
the trees 5 feet farther apart,he would need 44
fewer trees.If the farmer would take the advice,
how many trees would he plant?Answered by Penny Nom.

From John:I teach in a Faculty of Education. A colleague in the university asked me about fractions and lowest terms. I am quoting the person below, and would appreciate your insights into the question/thought.

"One I'm struggling with is why (for example) 6/18 is not considered as good an answer to a fraction question as 1/3. The traditional response is that 6/18 is not in lowest terms so the question has not been finished until the fraction is reduced, but what actually makes the lowest terms answer the better one? Is it convention? Is there a way to explain why simplest form answers in fractions are right and and anything else is considered incorrect without alluding to some need for this 'good habit' elsewhere in math or science? Is there a real-life reason?"
Thank you for any insights and if you have nothing to offer to this query, that is fine too. I appreciate your consideration.
JohnAnswered by Robert Dawson.

From Allen:An airplane whose capacity is 100 passengers is to be chartered for a flight to Europe. The fare is to be $150 per person, if 60 people buy tickets. However, the airline agrees to reduce the fare for every passenger by $1 for each additional ticket sold. How many tickets should be sold to maximize the ticket revenue for this flight?Answered by Chris Fisher.

From Anna:Hi, I need to find the the base and the height of a triangular prism, but I only know the diameter of a tennis ball that fits exactly in the triangular container.. The diameter for the ball is 8.50cm.
Can you help me find the formula?
Thank you!Answered by Penny Nom.